src/cons.handler.c

   1 /*
   2    Client interface for General purpose Linux console save/restore server
   3
   4    Copyright (C) 1994, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
   5    2006, 2007, 2011
   6    The Free Software Foundation, Inc.
   7
   8    This file is part of the Midnight Commander.
   9
  10    The Midnight Commander is free software: you can redistribute it
  11    and/or modify it under the terms of the GNU General Public License as
  12    published by the Free Software Foundation, either version 3 of the License,
  13    or (at your option) any later version.
  14
  15    The Midnight Commander is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 /** \file cons.handler.c
  25  *  \brief Source: client %interface for General purpose Linux console save/restore server
  26  */
  27
  28 #include <config.h>
  29
  30 #include <stdlib.h>
  31 #include <sys/wait.h>
  32 #include <signal.h>
  33 #include <stdio.h>
  34 #include <fcntl.h>
  35 #include <sys/types.h>
  36 #ifdef __FreeBSD__
  37 #include <sys/consio.h>
  38 #include <sys/ioctl.h>
  39 #endif
  40 #include <unistd.h>
  41
  42 #include "lib/global.h"
  43
  44 #include "lib/tty/tty.h"
  45 #include "lib/skin.h"           /* tty_set_normal_attrs */
  46 #include "lib/tty/win.h"
  47 #include "lib/util.h"           /* mc_build_filename() */
  48
  49 #include "consaver/cons.saver.h"
  50
  51 /*** global variables ****************************************************************************/
  52
  53 #ifdef __linux__
  54 int cons_saver_pid = 1;
  55 #endif /* __linux__ */
  56
  57 /*** file scope macro definitions ****************************************************************/
  58
  59 #if defined(__FreeBSD__)
  60 #define FD_OUT 1
  61 #define cursor_to(x, y) \
  62 do \
  63 { \
  64     printf("\x1B[%d;%df", (y) + 1, (x) + 1); \
  65     fflush(stdout); \
  66 } while (0)
  67 #endif /* __linux__ */
  68
  69 /*** file scope type declarations ****************************************************************/
  70
  71 /*** file scope variables ************************************************************************/
  72
  73 #ifdef __linux__
  74 /* The cons saver can't have a pid of 1, used to prevent bunches of
  75  * #ifdef linux */
  76 static int pipefd1[2] = { -1, -1 };
  77 static int pipefd2[2] = { -1, -1 };
  78 #elif defined(__FreeBSD__)
  79 static struct scrshot screen_shot;
  80 static struct vid_info screen_info;
  81 #endif /* __linux__ */
  82
  83 /*** file scope functions ************************************************************************/
  84 /* --------------------------------------------------------------------------------------------- */
  85
  86 #ifdef __linux__
  87 static void
  88 show_console_contents_linux (int starty, unsigned char begin_line, unsigned char end_line)
  89 {
  90     unsigned char message = 0;
  91     unsigned short bytes = 0;
  92     int i;
  93     ssize_t ret;
  94
  95     /* Is tty console? */
  96     if (mc_global.tty.console_flag == '\0')
  97         return;
  98     /* Paranoid: Is the cons.saver still running? */
  99     if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 100     {
 101         cons_saver_pid = 0;
 102         mc_global.tty.console_flag = '\0';
 103         return;
 104     }
 105
 106     /* Send command to the console handler */
 107     message = CONSOLE_CONTENTS;
 108     ret = write (pipefd1[1], &message, 1);
 109     /* Check for outdated cons.saver */
 110     ret = read (pipefd2[0], &message, 1);
 111     if (message != CONSOLE_CONTENTS)
 112         return;
 113
 114     /* Send the range of lines that we want */
 115     ret = write (pipefd1[1], &begin_line, 1);
 116     ret = write (pipefd1[1], &end_line, 1);
 117     /* Read the corresponding number of bytes */
 118     ret = read (pipefd2[0], &bytes, 2);
 119
 120     /* Read the bytes and output them */
 121     for (i = 0; i < bytes; i++)
 122     {
 123         if ((i % COLS) == 0)
 124             tty_gotoyx (starty + (i / COLS), 0);
 125         ret = read (pipefd2[0], &message, 1);
 126         tty_print_char (message);
 127     }
 128
 129     /* Read the value of the mc_global.tty.console_flag */
 130     ret = read (pipefd2[0], &message, 1);
 131 }
 132
 133 /* --------------------------------------------------------------------------------------------- */
 134
 135 static void
 136 handle_console_linux (console_action_t action)
 137 {
 138     char *tty_name;
 139     char *mc_conssaver;
 140     int status;
 141
 142     switch (action)
 143     {
 144     case CONSOLE_INIT:
 145         /* Close old pipe ends in case it is the 2nd time we run cons.saver */
 146         status = close (pipefd1[1]);
 147         status = close (pipefd2[0]);
 148         /* Create two pipes for communication */
 149         if (!((pipe (pipefd1) == 0) && ((pipe (pipefd2)) == 0)))
 150         {
 151             mc_global.tty.console_flag = '\0';
 152             break;
 153         }
 154         /* Get the console saver running */
 155         cons_saver_pid = fork ();
 156         if (cons_saver_pid < 0)
 157         {
 158             /* Cannot fork */
 159             /* Delete pipes */
 160             status = close (pipefd1[1]);
 161             status = close (pipefd1[0]);
 162             status = close (pipefd2[1]);
 163             status = close (pipefd2[0]);
 164             mc_global.tty.console_flag = '\0';
 165         }
 166         else if (cons_saver_pid > 0)
 167         {
 168             /* Parent */
 169             /* Close the extra pipe ends */
 170             status = close (pipefd1[0]);
 171             status = close (pipefd2[1]);
 172             /* Was the child successful? */
 173             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 174             if (mc_global.tty.console_flag == '\0')
 175             {
 176                 pid_t ret;
 177                 status = close (pipefd1[1]);
 178                 status = close (pipefd2[0]);
 179                 ret = waitpid (cons_saver_pid, &status, 0);
 180             }
 181         }
 182         else
 183         {
 184             /* Child */
 185             /* Close the extra pipe ends */
 186             status = close (pipefd1[1]);
 187             status = close (pipefd2[0]);
 188             tty_name = ttyname (0);
 189             /* Bind the pipe 0 to the standard input */
 190             do
 191             {
 192                 if (dup2 (pipefd1[0], 0) == -1)
 193                     break;
 194                 status = close (pipefd1[0]);
 195                 /* Bind the pipe 1 to the standard output */
 196                 if (dup2 (pipefd2[1], 1) == -1)
 197                     break;
 198
 199                 status = close (pipefd2[1]);
 200                 /* Bind standard error to /dev/null */
 201                 status = open ("/dev/null", O_WRONLY);
 202                 if (dup2 (status, 2) == -1)
 203                     break;
 204                 status = close (status);
 205                 if (tty_name)
 206                 {
 207                     /* Exec the console save/restore handler */
 208                     mc_conssaver = mc_build_filename (SAVERDIR, "cons.saver", NULL);
 209                     execl (mc_conssaver, "cons.saver", tty_name, (char *) NULL);
 210                 }
 211                 /* Console is not a tty or execl() failed */
 212             }
 213             while (0);
 214             mc_global.tty.console_flag = '\0';
 215             status = write (1, &mc_global.tty.console_flag, 1);
 216             _exit (3);
 217         }                       /* if (cons_saver_pid ...) */
 218         break;
 219
 220     case CONSOLE_DONE:
 221     case CONSOLE_SAVE:
 222     case CONSOLE_RESTORE:
 223         /* Is tty console? */
 224         if (mc_global.tty.console_flag == '\0')
 225             return;
 226         /* Paranoid: Is the cons.saver still running? */
 227         if (cons_saver_pid < 1 || kill (cons_saver_pid, SIGCONT))
 228         {
 229             cons_saver_pid = 0;
 230             mc_global.tty.console_flag = '\0';
 231             return;
 232         }
 233         /* Send command to the console handler */
 234         status = write (pipefd1[1], &action, 1);
 235         if (action != CONSOLE_DONE)
 236         {
 237             /* Wait the console handler to do its job */
 238             status = read (pipefd2[0], &mc_global.tty.console_flag, 1);
 239         }
 240         if (action == CONSOLE_DONE || mc_global.tty.console_flag == '\0')
 241         {
 242             /* We are done -> Let's clean up */
 243             pid_t ret;
 244             close (pipefd1[1]);
 245             close (pipefd2[0]);
 246             ret = waitpid (cons_saver_pid, &status, 0);
 247             mc_global.tty.console_flag = '\0';
 248         }
 249         break;
 250     default:
 251         break;
 252     }
 253 }
 254
 255 #elif defined(__FreeBSD__)
 256
 257 /* --------------------------------------------------------------------------------------------- */
 258 /**
 259  * FreeBSD support copyright (C) 2003 Alexander Serkov <serkov@ukrpost.net>.
 260  * Support for screenmaps by Max Khon <fjoe@FreeBSD.org>
 261  */
 262
 263 static void
 264 console_init (void)
 265 {
 266     if (mc_global.tty.console_flag != '\0')
 267         return;
 268
 269     screen_info.size = sizeof (screen_info);
 270     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 271         return;
 272
 273     memset (&screen_shot, 0, sizeof (screen_shot));
 274     screen_shot.xsize = screen_info.mv_csz;
 275     screen_shot.ysize = screen_info.mv_rsz;
 276     screen_shot.buf = g_try_malloc (screen_info.mv_csz * screen_info.mv_rsz * 2);
 277     if (screen_shot.buf != NULL)
 278         mc_global.tty.console_flag = '\001';
 279 }
 280
 281 /* --------------------------------------------------------------------------------------------- */
 282
 283 static void
 284 set_attr (unsigned attr)
 285 {
 286     /*
 287      * Convert color indices returned by SCRSHOT (red=4, green=2, blue=1)
 288      * to indices for ANSI sequences (red=1, green=2, blue=4).
 289      */
 290     static const int color_map[8] = { 0, 4, 2, 6, 1, 5, 3, 7 };
 291     int bc, tc;
 292
 293     tc = attr & 0xF;
 294     bc = (attr >> 4) & 0xF;
 295
 296     printf ("\x1B[%d;%d;3%d;4%dm", (bc & 8) ? 5 : 25, (tc & 8) ? 1 : 22,
 297             color_map[tc & 7], color_map[bc & 7]);
 298 }
 299
 300 /* --------------------------------------------------------------------------------------------- */
 301
 302 static void
 303 console_restore (void)
 304 {
 305     int i, last;
 306
 307     if (mc_global.tty.console_flag == '\0')
 308         return;
 309
 310     cursor_to (0, 0);
 311
 312     /* restoring all content up to cursor position */
 313     last = screen_info.mv_row * screen_info.mv_csz + screen_info.mv_col;
 314     for (i = 0; i < last; ++i)
 315     {
 316         set_attr ((screen_shot.buf[i] >> 8) & 0xFF);
 317         putc (screen_shot.buf[i] & 0xFF, stdout);
 318     }
 319
 320     /* restoring cursor color */
 321     set_attr ((screen_shot.buf[last] >> 8) & 0xFF);
 322
 323     fflush (stdout);
 324 }
 325
 326 /* --------------------------------------------------------------------------------------------- */
 327
 328 static void
 329 console_shutdown (void)
 330 {
 331     if (mc_global.tty.console_flag == '\0')
 332         return;
 333
 334     g_free (screen_shot.buf);
 335
 336     mc_global.tty.console_flag = '\0';
 337 }
 338
 339 /* --------------------------------------------------------------------------------------------- */
 340
 341 static void
 342 console_save (void)
 343 {
 344     int i;
 345     scrmap_t map;
 346     scrmap_t revmap;
 347
 348     if (mc_global.tty.console_flag == '\0')
 349         return;
 350
 351     /* screen_info.size is already set in console_init() */
 352     if (ioctl (FD_OUT, CONS_GETINFO, &screen_info) == -1)
 353     {
 354         console_shutdown ();
 355         return;
 356     }
 357
 358     /* handle console resize */
 359     if (screen_info.mv_csz != screen_shot.xsize || screen_info.mv_rsz != screen_shot.ysize)
 360     {
 361         console_shutdown ();
 362         console_init ();
 363     }
 364
 365     if (ioctl (FD_OUT, CONS_SCRSHOT, &screen_shot) == -1)
 366     {
 367         console_shutdown ();
 368         return;
 369     }
 370
 371     if (ioctl (FD_OUT, GIO_SCRNMAP, &map) == -1)
 372     {
 373         console_shutdown ();
 374         return;
 375     }
 376
 377     for (i = 0; i < 256; i++)
 378     {
 379         char *p = memchr (map.scrmap, i, 256);
 380         revmap.scrmap[i] = p ? p - map.scrmap : i;
 381     }
 382
 383     for (i = 0; i < screen_shot.xsize * screen_shot.ysize; i++)
 384     {
 385         screen_shot.buf[i] =
 386             (screen_shot.buf[i] & 0xff00) | (unsigned char) revmap.
 387             scrmap[screen_shot.buf[i] & 0xff];
 388     }
 389 }
 390
 391 /* --------------------------------------------------------------------------------------------- */
 392
 393 static void
 394 show_console_contents_freebsd (int starty, unsigned char begin_line, unsigned char end_line)
 395 {
 396     int col, line;
 397     char c;
 398
 399     if (mc_global.tty.console_flag == '\0')
 400         return;
 401
 402     for (line = begin_line; line <= end_line; line++)
 403     {
 404         tty_gotoyx (starty + line - begin_line, 0);
 405         for (col = 0; col < min (COLS, screen_info.mv_csz); col++)
 406         {
 407             c = screen_shot.buf[line * screen_info.mv_csz + col] & 0xFF;
 408             tty_print_char (c);
 409         }
 410     }
 411 }
 412
 413 /* --------------------------------------------------------------------------------------------- */
 414
 415 static void
 416 handle_console_freebsd (console_action_t action)
 417 {
 418     switch (action)
 419     {
 420     case CONSOLE_INIT:
 421         console_init ();
 422         break;
 423
 424     case CONSOLE_DONE:
 425         console_shutdown ();
 426         break;
 427
 428     case CONSOLE_SAVE:
 429         console_save ();
 430         break;
 431
 432     case CONSOLE_RESTORE:
 433         console_restore ();
 434         break;
 435     default:
 436         break;
 437     }
 438 }
 439 #endif /* __FreeBSD__ */
 440
 441 /* --------------------------------------------------------------------------------------------- */
 442 /*** public functions ****************************************************************************/
 443 /* --------------------------------------------------------------------------------------------- */
 444
 445 void
 446 show_console_contents (int starty, unsigned char begin_line, unsigned char end_line)
 447 {
 448     tty_set_normal_attrs ();
 449
 450     if (look_for_rxvt_extensions ())
 451     {
 452         show_rxvt_contents (starty, begin_line, end_line);
 453         return;
 454     }
 455 #ifdef __linux__
 456     show_console_contents_linux (starty, begin_line, end_line);
 457 #elif defined (__FreeBSD__)
 458     show_console_contents_freebsd (starty, begin_line, end_line);
 459 #else
 460     mc_global.tty.console_flag = '\0';
 461 #endif
 462 }
 463
 464 /* --------------------------------------------------------------------------------------------- */
 465
 466 void
 467 handle_console (console_action_t action)
 468 {
 469     (void) action;
 470
 471     if (look_for_rxvt_extensions ())
 472         return;
 473
 474 #ifdef __linux__
 475     handle_console_linux (action);
 476 #elif defined (__FreeBSD__)
 477     handle_console_freebsd (action);
 478 #endif
 479 }
 480
 481 /* --------------------------------------------------------------------------------------------- */